Sierra 18-99410 Johnson Evinrude Timer Base, 6 Cylinder, Replaces 763774 584363 583853, Fits 1989-1992 150-175 HP

The Sierra 18-99410 is a replacement timer base for 6 cylinder Johnson/Evinrude Cross Flow outboard engines equipped with Quick Start and S.L.O.W. Ignition systems. The timer base is a core ignition component that controls spark timing as the engine rotates, and a worn or failing unit can cause hard starting, misfires, or inconsistent timing across cylinders. Installing the Sierra 18-99410 restores the original timing signal path so the ignition system fires each cylinder at the correct point in the engine cycle.

This timer base fits 1989-1992 6 cylinder Cross Flow engines rated 150, 155, and 175 HP. It directly replaces OEM numbers 763774, 584363, and 583853, so it installs in place of the original part without modification. The unit weighs 0.9 pounds.

Specifications

• Brand: Sierra
• Manufacturer Part Number: 18-99410
• Category: Evinrude Outboard Ignition System
• UPC: 808282394417
• Weight: 0.9 pounds
• Cylinders: 6
• Engine Type: Cross Flow with Quick Start and S.L.O.W.

Fitment

• Johnson/Evinrude 1989-1992, 6 cylinder Cross Flow engines with Quick Start and S.L.O.W., 150, 155, and 175 HP

Replaces (OEM)

• 763774
• 584363
• 583853

Frequently Asked Questions

What engines does the Sierra 18-99410 timer base fit? The Sierra 18-99410 timer base fits 1989-1992 6 cylinder Johnson/Evinrude Cross Flow engines equipped with Quick Start and S.L.O.W., rated 150, 155, and 175 HP.

What OEM part numbers does this timer base replace? This timer base replaces OEM numbers 763774, 584363, and 583853.

How much does the Sierra 18-99410 weigh? The Sierra 18-99410 timer base weighs 0.9 pounds.

Is the Sierra 18-99410 a direct replacement for the original timer base? Yes, the Sierra 18-99410 is designed as a direct replacement, installing in place of the original 763774, 584363, or 583853 timer base without modification.

Does this timer base work with a 4 cylinder outboard? No, the Sierra 18-99410 is built for 6 cylinder Johnson/Evinrude Cross Flow engines, not 4 cylinder applications.

What ignition system must my engine have for this timer base to fit? Your engine needs the Quick Start and S.L.O.W. Ignition system found on the covered 6 cylinder Cross Flow Johnson/Evinrude engines to use the Sierra 18-99410.

What symptoms indicate my timer base needs replacement? Hard starting, misfires, or inconsistent spark timing on a 6 cylinder Johnson/Evinrude Cross Flow engine are common signs that the timer base, such as the Sierra 18-99410, needs replacing.

What horsepower ratings does the 18-99410 cover? The Sierra 18-99410 is built for 150, 155, and 175 HP versions of the 1989-1992 6 cylinder Cross Flow engine.

Is the UPC for this part 808282394417? Yes, the Sierra 18-99410 timer base carries UPC 808282394417.

Can I cross-reference this part using my old timer base number? Yes, if your old timer base is stamped 763774, 584363, or 583853, the Sierra 18-99410 is the correct replacement.